Microchip Technology dsPIC30F - dsPIC QEI Features Overview; QEI Signal Decoding and Accumulation; Input Swapping and Noise Filters; Counting Modes and Registers

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© 2004 Microchip Technology Incorporated. All Rights Reserved. Introduction to the dsPIC30F Architecture (Part 2) 5
Program Memory Organization*
Reset Vector-
GOTO instruction
User Flash
Program Memory
(~48K Instructions)
Configuration
Memory Space
0x000100
0x00007E
0x017FFE
0x800000
0xFFFFFE
0x000000
Interrupt Vector Table
(0x000004 - 0x00007E)
Program Instructions
(0x000100 - 0x017FFE)
Configuration Memory
Executable code starts at 0x100
Alternate
Vector Table
0x018000
0x7FF000
Data EEPROM
(4 K Bytes)
0x000084
0x0000FE
Reserved
Interrupt
Vector Table
Reserved
0x000002
* Sample Program
Memory Map shown
here for dsPIC30F6014
device
0x000004
The Program Memory map of the dsPIC30F includes the reset vector, interrupt
vector table, an alternate vector table, user Program Flash memory, Data
EEPROM and configuration memory space.
The Reset Vector is a 2 word GOTO instruction, and is therefore the only vector
that occupies two words. All interrupt vector locations are filled with their
respective interrupt service routine or ISR addresses, if an ISRis defined. There is
an alternate vector table that can optionally be enabled by the user. It provides a
complete set of all interrupt vectors, and is a useful aid during system debug.
The executable 24-bit wide Program Flash memory starts at hex 100 in all
dsPIC30F devices and progresses linearly through the program address space.
The 16-bit wide Data EEPROM block resides in the upper end of the user
program memory space, and is accessible using table instructions or a feature
called Program Space Visibility. The Data EEPROM can be used for storing
application constants and other parametric data such as lookup tables and sensor
calibration constants.
Finally, the Program Memory map includes configuration memory space, which
can only be accessed using the table instructions. The Device Configuration
Registers, which are used to configure basic parameters of device operation such
as system clock source, are located in this address space.
The sample program memory map shown above is for the dsPIC30F6014 device
and will, of course, vary from one device to another.
Note that unlike PIC
®
MCU architectures, paging of program memory is not
required with the dsPIC30F.